| US 7,488,421 B2 | ||
| Method and device for the purification, especially desalination, of water | ||
| Guenther Hambitzer, Pfinztal (Germany); Heide Biollaz, Waldshut (Germany); Markus Borck, Stuttgart (Germany); and Christiane Ripp, Pfinztal (Germany) | ||
| Assigned to Clean Water Gesellschaft Fuer Wasseraufbereitungstechnik mbH, Pfinztal (Germany) | ||
| Appl. No. 10/556,363 PCT Filed Apr. 24, 2004, PCT No. PCT/DE2004/000855 § 371(c)(1), (2), (4) Date Nov. 10, 2005, PCT Pub. No. WO2004/101444, PCT Pub. Date Nov. 25, 2004. |
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| Claims priority of application No. 103 21 146 (DE), filed on Mar. 12, 2003. | ||
| Prior Publication US 2006/0108286 A1, May 25, 2006 | ||
| Int. Cl. B01D 15/00 (2006.01); B01D 1/28 (2006.01); B01D 3/00 (2006.01); C02F 17/09 (2006.01); C02F 1/02 (2006.01); B01J 35/00 (2006.01) | ||
| U.S. Cl. 210—640 [210/175; 210/181; 204/158.2; 204/450; 204/554; 204/403.06; 202/82; 202/266; 202/181; 203/10; 203/12] | 30 Claims |
| 1. Water processing method, by means of membrane distillation, wherein
the water to be processed is held in a supply chamber, a wall of which is formed at least in part by a stack of membrane layers
which are permeable to water vapor, said stack comprising a hydrophobic membrane and a hydrophilic membrane, wherein the hydrophilic
membrane runs parallel to the hydrophobic membrane and is located on the side of the hydrophobic membrane that is remote from
the water to be processed,
the hydrophilic membrane has a greater thickness in comparison with the hydrophobic membrane,
the hydrophilic membrane has a lower thermal conduction per unit area in comparison with the hydrophobic membrane,
a vapor pressure difference between the water to be processed and condensed water is created by a pumping action so that the
membrane distillation is driven by the vapor pressure difference resulting from the pumping action, the water condensing in
the pores of the hydrophilic membrane,
the water pressure difference is at least partially created by the fact that the condensed water is pumped out of the hydrophilic
membrane by a micropump method including a force acting on the water molecules in the pores of the hydrophilic membrane, and
wherein, in order to provide an electro-osmotic pump action, two flat electrodes are arranged in parallel with the hydrophilic
membranes such that at least a layer of the hydrophilic membrane runs between the two electrodes.
|